Dynamically balanced rotor



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Feb. 5, 1952 Filed April 18, 1949 E. L. TH EARLE DYNAMICALLY BALANCEDROTOR MIT/q:

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59/755 T L. THi-APH- Feb. 5, 1952 E. L. THEARLE 2,584,942

DYNAMICALLY BALANCED ROTOR Filed April 18, 1949 I I 4 Sheets-Sheet 2fifie F INVENTOR.

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E. L. THEARLE DYNAMICALLY BALANCED ROTOR Feb. 5, 1952 Filed April 18,1949 4 Sheets-Sheet 4 INVENTOR. hwsr L, mm:-

Armum Patented Feb. 5, 1952 UNITED STATES PATENT OFFICE DYNAMICALLYBALANCED ROTOR Ernest L. Thearle, Palo Alto, Calif.

Application April 18, 1949, Serial No. 88,067

24 Claims.

Thi invention relates in general to rotating equipment such as forexample domestic centrifugal clothes extractors, and more particularlyto devices of this character provided with automatic means for bringingthem into and maintaining them in dynamic balance.

As is well known in the trade, many centrifugal extractors for expellingwater from laundered clothes are subject to 'such excessive vibrationwhen in operation that most, if not all, apart-i ment houses precludetheir installation above the ground floor. This of course results fromthe unequal distribution of the clothes within the extractor, acondition over which the operator has no control in the case ofautomatic clock-controlled washer-extractor combinations. Althoughvarious expedients have been resorted to in attempting to overcome thisproblem, none of them has been entirely satisfactory. Among the mostsuccessful of such expedients is the provision of peripherally spaced,longitudinally extending balancing pockets formed about the extractortub or basket in conjunction with valve means responsive to the gyratorymovement of the shaft on which the basket is mounted and whichselectively delivers balancing water to one or more of the pockets lyingdiametrically opposite to the direction of the eccentricity of thebasket. Although this to some extent aids in bringing the basket intodynamic balance, it falls considerably short of its intended purpose.For one reason, this is due to the fact that to bring about an actualdynamic balance, the balancing fluid should not be supplied to thebasket at a point diametrically opposite to the direction of itseccentricity, but rather at a point diametrically. opposite from thepoint at which the unbalancing load is concentrated.

As is known to those conversant with the behavior and mechanics ofcentrifugal equipment, and as presently will be more fully explained,any point on the geometric axis of a rotor, when rotating at a constantspeed and under the influence of an unbalancing weight, is displacedfrom its spin axis and describes a circular path about its spin axishaving a radius equal to its displacement or eccentricity. Contrary towhat normally might be expected, the direction of this displacement oreccentricity is not in radial alignment with the unbalancing weight, butinstead is angularly offset by what may be referred to as the angle oflag. Furthermore, both the eccentricity and the angle of lag vary withthe speed of rotation. It will be seen therefore that to bring a rotorinto dynamic balance, all of these factors must be taken intoconsideration.

In general, then, the object of this invention is the provision incombination with a rotor of a balancing device sensitive and responsiveto variations in the eccentricity of the rotor and in the angle of lagof the eccentricity, for adding a balancing fluid to therotor at a pointsubstantially diametrically opposite the unbalancing load.

More specifically, the object of this invention is the provision incombination with a rotor provided with peripherally spaced,longitudinally extending unbalacing pockets, of an automatic distributoroperating in response to variations in the eccentricity of the rotor andthe angle of lag of the eccentricity, for adding balancing fluid to saidpockets at a point diametrically opposite the unbalancing load.

A further object oi this invention is the provision of a distributor ofthe character above described in combination with a centrifugal rotordesigned to rotate on either a vertical or a horizontal axis.

The invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the following descriptionwhere those forms of the invention which have been selected forillustration in the drawings accompanying and forming a part of thepresent specification are outlined in full. In said drawings, two formsof the invention are shown, but it is to be understood that it is notlimited to such forms, since the invention as set forth in the claimsmay be embodied in a plurality of forms.

Referring to the drawings:

Fig. 1 is a diagrammatic elevation of a free spindle rotor assemblyshowing its action when not in dynamic balance.

Fig. 2 is a transverse section taken on the section line 22 of Fig. 1.

Fig. 3 is a graph showing the relation between the speed of rotation ofa rotor and its eccentricity resulting from an out-of-balance condition.

Fig. 4 is a graph showing the relation between the speed of rotation ofa rotor and the angle of lag of its eccentricity resulting from anout-ofbalance condition.

Fig. 5 is a diagrammatic illustration of an unbalanced rotor to behereinafter used in conjunction with Fig. 6 to illustrate theeffectiveness and efiiciency obtained in applying a counterbalancingweight progressively at different points on the rotor.

Fig. 6 is a vector diagram illustrating the progressively incrementalbalancing of a rotor.

Fig. 7 is a mid vertical section of a clothes extractor embodying theobjects of my invention and arranged to rotate on a vertical axis.

Fig. 8 is a horizontal section taken on the section line 8-4 of Fig. '7.

Fig. 9 is a fragmentary longitudinal section similar to the sectionillustrated in Fig. '7 but wherein the objects of my invention have beenembodied in a rotor arranged to rotate on a horizontal axis rather thanon a vertical axis.

Fig. 10 is a section taken on the section line |-l0 of Fig. 9.

Fig. 11 is an enlarged detail of the deflecting vanes and associatedstructures forming a part of the device shown in Figs. 9 and 10.

Fig. 12 is a section taken on the section line l2i2 of Fig. 11, butshowing the deflecting louvers in the position assumed thereby when therotor is rotating at speeds above the transition speed.

Since as above indicated the construction and operation of the balancingmechanismsincorporated in the devices shown in Figs. 7 to 12 inclusivedepend upon the mechanics and behavior of a free spindle rotor operatingat speeds at which centrifugal force becomes a factor, a more detailedconsideration thereof should be helpful in gaining an appreciation ofthe construction and function of these devices. For this purpose,reference is had to Figs. 1 to 6 inclusive.

The free spindle rotor assembly illustrated in Figs. 1 and 2 includes byway of example an extractor basket or tub B of conventional form mountedon the upper end of a substantially rigid shaft E. The lower end of thisshaft is fixed to or serves as the shaft of a motor D resiliently orflexibly mounted through springs F on a frame or base G. In effect,then, the shaft E has a universal connection with the frame G andconsequently the shaft and its basket are free to gyrate about the fixedreference axis or axis of rotation O, and may be considered as a freespindle system.

If the basket B is in dynamic balance and rotating at a constant speed,the geometric center C of the basket will coincide with the spin axis oraxis of rotation O, and as a consequence the system will be free ofvibration. If, however, it be assumed that the basket B is not indynamic balance due to an unbalance weight W, the geometric center C ofthe basket will be defiected a distance e, from the axis of rotation,and describe a circular path p of radius e. From an inspection of Fig. 2it will be seen that contrary to popular conception, the direction ofthis deflection. or eccentricity e does not coincide with the directionof the unbalance weight W, but instead lags behind it by an angle thisangle being hereinafter referred to as the "angle of lag. As shown inFigs. 3 and 4, the eccentricity e, and the angle of lag 9S, vary withthe speed of rotation N of the rotor. These relations can bedemonstrated experimentally or analytically and are well known to theart as is evidenced by the following publication: "A new type of dynamicbalancing machine, by E. L. Thearle, A. S. M. E. Trans, vol. 54, pp.131-141, 1932, A. P. M. section. Also as set forth by the same author inhis rticle entitled The rotating disk," appearing in the November 1924issue of Mechanical Engineering, the amount of dampening in the systemand the angular acceleration of the rotor have some influence on theshapes or proportions of the graphs shown in Figs. 3 and 4.

By reference to Fig. 3 it will be seen that the eccentricity, e, orradius of whirl of an unbalanced rotor, increases with speed and reachesa maximum at about the critical, or resonant speed of the system. Abovethis speed it then decreases and approaches the eccentricity of thecenter of gravity of the basket and its unbalance load. As shown in Fig.4, the angle of lag, 0, is zero at zero speed, increases with speed to avalue of at the critical speed, and approaches 180 at infinite speed.

From these considerations it is apparent that a satisfactory automaticbalancing device must:

1. Be operative at speeds below, at, and above its critical speed.

2. Be sensitive and responsive to the amount of eccentricity andperforce the amount of unbalance so as immediately to bring the systeminto dynamic balance and maintain it in such balance.

3. Be sensitive and responsive to variations in the angle of lag so asto be operative below, at. and above the critical speed of the system.

superficially it may be thought that, in order to meet theserequirements, an automatic balancer should operate to add each incrementof balancing weight at a point exactly diametrically opposite theunbalancing weight. This, however, is not the case, as will becomeapparent from a consideration of Fig. 5. In this figure, W representsthe unbalance in the system and since unbalance has direction as well asmagnitude it can be represented by the vector O-H indicated in Fig. 6.Now assume that the balancing device, during any small interval of time,adds an increment of corrective weight, dw, not at a point diametricallyopposite the unbalance, but at an angle 6 (angle of error) from thispoint, this increment of correction dw, being indicated as the vectorH-J in Fig. 6. The next increment of correction, vector J--K, will thenbe added at an angle of error6 from the vector 0--J to compensate forthe resultant of the initial unbalance W and the first increment ofcorrection H4. From this it can be seen that a balanced condition willalways be approached along a logarithmic spiral if the angle of error 6is less than 90 as illustrated in Fig. 6. Therefore, the effectivenessof an automatic balancer meeting the conditions above set forth is solong as the mean angle of error, 6 is less than 90.

To determine the efliciency of such a balancer as distinguished from itseffectiveness, reference is had to Fig. 6 from which it will be seenthat:

1 dW=dw cos 6 Assuming a constant angle of error, or using 6 in thesense of a mean angle of error, Equation 1 integrates into:

2 W=w cos 6 If W=the original unbalance, in pound inches,

then w=the required balance-correction in pound inches and if theefllciency of the balancer be defined as W/w, then Equation 2 showsthat:

3 Eiliciency=cos 6 Thus, for example, if the mean angle of error is 30,and the correction is added at the same radius as the initial unbalance,each pound of corrective fluid will perfectly balance 00.866 pound ofinitial unbalance. This difference is due to the distribution orlocation of the corrective balance weight.

The fact that the efflciency of such a balancer is less than 100% doesnot detract from its value, for it is nevertheless 100% effective.

Automatic dynamic balancers operating in accordance with the aboveprinciples have been embodied by way of example in the two forms ofcentrifugal extractors diagrammatically illustrated in Figs. '1 to 12inclusive. Both of these modifications include a free spindle type ofextractor basket provided with longitudinally extending, peripherallyspaced balancing pockets; 8. segmented distributing disk for selectivelyslinging balancing fluid to conduits communicating with the balancingpockets. and an automatic valve operative in response to thedisplacement of the basket for selectively delivering balancing fluidfrom a source of such fluid to one or more of the segments of thedistributing disk.

The modification shown in Figs. 7 and 8 is designed to rotate on avertical axis and in this modification gravity is utilized for makingthe balancer sensitive and selectively responsive to variations in thespeed of rotation of the basket.

In the modification illustrated in Figs. 9, 10, 1i and 12 and designedto operate on a horizontal axis, centrifugal force is utilized formaking the balancer sensitive and selectively responsive to variationsin the speed of rotation of the basket.

The extractor illustrated in Figs. '7 and 8 includes a shell or casin Iprovided at its lower end with a plurality of inwardly extendingbrackets 2. Mounted on the inner ends of these brackets through themedium of rubber blocks 3 is a motor a including a vertical shaftextending upwardly through a relatively large central opening 8 formedin the casing bottom I. Fixed to the upper end of the shaft is anextractor tub or basket 8 terminating at its upper peripheral edge in.an outwardly and downwardly turned lip 9. Formed integral with thebasket 8 about its outer periphery are a series or plurality ofbalancing pockets Ila through I I f formed by a common circular wall I2coaxial with the basket 8 and by radial partitions I3 extending betweenthe basket 8 and the circular wall I2. Surrounding the wall I2 andformed integral with the shell or casing I is an annular trough orreservoir It for the accommodation of a supply of water I5 or otherbalancing fluid.

Mounted or formed on the bottom I6 of the basket 8 is a balancing fluiddistributing disk or slinger generally designated by the referencenumeral i1, and defined by an annular bottom plate I8 and byperipherally spaced circular walls I9 and 20. Extending between thebottom I8 of the distributing disk and the bottom I6 of the basket,which serves as the upper wall of the disk, is a plurality ofsymmetrically and spirally disposed webs or vanes 2| dividing the diskinto a plurality of generally spiral fluid channels 22a through 22!.angularly ofiset in a direction opposite to the direction of rotation ofthe basket as indicated in Fig. 8. Formed at the inner ends of therespective channels 220. through 22! are inlet ports 2341 through 23 andformed on the outer ends of each of these channels are fluid outletports 2441 through 24f respectively. From an inspection of Fig. 8 itwill be seen that the outlet ports of each of these channels isangularly offset in a direction opposite to the direction of rotation ofthe basket with respect to its inlet port, that each of the outlet portsare in radial alignment with one of the partitions I3 and that itsassociated inlet port is slightly radially oiiset with respect to thenext counter-clockwise succeeding partition I3.

Fastened to the side walls of the shell I and extending inwardly thereofare brackets 25 and secured to the inner end of each of these bracketsis a spring finger 26. Fastened to the inner ends of these springfingers is a channel supply ring 21, arranged to have sealing engagementwith the bottom I 8 of the distributor I1 and to form an automatic valvetherewith. Due to this method of mounting the supply ring 21, it isfixed against rotary and radial motion but free to nod in response toany gyratory movement of the basket resulting from its out-of-balance.Connecting the trough or reservoir I4 with the ring 21 is a hose 28 ofsuflicient length and flexibility to permit the free tilting movement ofthe ring 21.

It is important to note from an inspection of Fig. '7 that the innerwall 21a of the ring 21 is formed on a radius approximately equal to theinner radius of the ports 23a through 233, is of a thickness somewhatgreater than the width of these ports, and that consequently when thesystem is static or in dynamic balance all of the ports 23a through 231will be closed by this wall of the channel. Under these conditions therewill be no communication between the supply ring 21 and the distributingdisk and slinger II. If, however, the basket is displaced to the rightas viewed in Figs. 7 and-8 under the influence of an unbalancing load,the distributing disk being fixed to the basket will also move to theright thereby bringing one or more of its inlet ports into registrationwith the supply ring and thereby permitting the flow of balancing fluidfrom the reservoir I4 through the hose section 28 and through the ring21 into one or more of the corresponding segments of the distributingdisk II.

Although the upper ends of the balancing pockets II are closed by acontinuation of the common annular wall I2, their lower ends areprovided with ports 29 on substantially the level of the distributingdisk I! and with the supply ring 21. Disposed between the basket bottomI6 and the lower horizontal ends of the circular wall [2 is a transverseannular plate 30 dividing the ports 29 into upper and lower portsections 3Ia and Mb. Extending between the bottom I6 of the basket andthe plate 30 are vertical baflies 32 forming an extension of the radialpartitions I3 and angularly oiiset' in the direction of rotation of thebasket 8. The bottom I6 of the basket, the plate 30 and each adjacentpair of the baflies 32 therefore define a series of angularly ofisetconduits 33a through 33f communicating at their outer ends with theupper port sectors 3Ia of the balancing pocket ports 29 and terminatingat their inner ends in open sectors subtending and in angular alignmentrespectively with the outlet ports 25a to 24) of the distributing disk Hbut radially spaced therefrom. Similarly disposed between the plate 30and the lower end of the wall I2 are vertically disposed bafiles 34forming a continuation of the partitions I3 but angularly offset in adirection opposite to the direction of rotation of the basket 8. Eachpair of adjacent, bafiles 34, together with the plate 30 and the bottomportion of the wall I2, define a series of conduits 35a through 35communicating at their outer ends respectively with one of the lowerport sectors 3Ib of the pockets II and terminating at their inner endsin open sectors lying adjacent to but below the distributing disk I1 andin angular alignment with one of the outlet ports 24 thereof. Waterentering one of the inlet ports 23 therefore travels spirally in aclockwise direction through one of the channels 22, passes outwardlythrough the corresponding 76 outlet port 24, and then depending upon thespeed of rotation of the basket, passes to one or the other of thebalancing pockets formed on either side of that particular radial walll3 lying in substantial angular alignment with the outlet port 24 underconsideration. If the basket is rtating at low speeds, the water onleaving the ports 24 will be subjected to the action of gravity for asufficient length of time to cause it to drop into one of the lowerradially aligned conduits 35. At high speeds the water enters thebalancing pocket I I through one of the upper channels. Depending thenon the speed of rotation, the water can be given either a positive ornegative lag relative to the corresponding outlet port 24.

Now assume that at some instant under consideration the basket 8 due toan unbalance weight as viewed in Fig. 8, has been displaced to the rightand that consequently balancing water is entering the port 23a of thedistributing disk and being slung radially therefrom through itsdischarge port 24a. Depending upon the speed of rotation of the basket,the water leaving the discharge port will pass through the conduit 35ainto the pocket Ii a or through the conduit 33a into the next succeedingpocket I If in the direction of rotation of the basket. In connectionwith the following description of the operation of this device it shouldbe noted that the term "transition speed is used to denote that speed atwhich the centrifugal force at which the bal ancing water is slungoutwardly from the distributing disk is sufficient to overcome theaction of gravity in the first modification and in the secondmodification the speed at which the centrifugal force becomes effectiveto rotate the deflecting louvers against the action of their biasingsprings. If the basket is rotating at a speed below the transition speedit will take the former path for there is then 'suflicient time forgravity to draw it into the lower conduit. In on the other hand thebasket is traveling at a speed above the transition speed, the waterwill be slung into the upper conduit before gravity has had sufficienttime to deflect it downwardly into the lower conduit. At the transitionspeed the water may of course be split between the two conduits. It willtherefore be seen that regardless of the speed of rotation, thebalancing water in passing through the distributing disk is deflected ina direction opposite to the direction of rotation of the basket throughthe angle subtending the inlet and discharge ports of distributing diskchannels 22 and which may be referred to as the distributing disk anglea. Independently of this deflection, and superposed thereon selectivelyin response to the speed of rotation of the basket is an additionalangle of lag 8 to which the balancing water is subjected in passing fromthe distributing disk into the balancing pockets ll. As above indicated,this latter deflection may be either positive, that is additive to a atspeeds below the transition speed to correct for the low angle of lag ofthe eccentricity at low speeds or it can be negative when the basket isrotating at speeds above the transition speed to correct for the greaterangle of lag of the eccentricity occurring at these speeds. It shouldhere be noted that the inner diameter of the horizontal portion of thepocket wall i2 serving as the bottom of the lower conduits 33, can be sochosen that the balancer becomes effective only above a selected speedof rotation of the basket. Also the inner diameter of the plate 30determines the transitional speed at which the balancing water is slungthrough the upper conduits to the balancing pockets rather than throughthe lower conduits.

The relations existing between the various angles above referred to areas follows:

(Above the transition speed) 4. +a-fi+6=180 (Below the transition speed)5. +a+fl+5=180 In the balancer illustrated in Figs. 7 and 8 and belowthe transition speed a=, and +fl=+30 Substituting the values in Equation5 gives Thus the angle of error, 6, is zero when the angle of lag of theeccentricity, is 75 and this occurs when the basket is rotating somewhatbelow its critical speed.

Above the transition speed:

1:75, and -p=-30 Substituting these values in Equation; gives Here theangle of error is zero when the angle of lag of the eccentricity is andthis occurs when the basket is rotating at a speed somewhat above itscritical speed. With this particular design, the eilectiveness" willalways be 100% and since the angle of error will always be less than 45,the efiiciency will always be greater than 70%.

Although the balancer above described has been shown as provided withsix balancing pockets any number greater than two are operative. Itshould also be noted that it is not necessary as shown in Fig. 8, thatthe change in the angle of lag to which the balancing fluid is subjected(213) be equal to the angle subtended by each of the balancing pockets(here 60'). This angle, 218 may be that subtended by any desired numberof balancing pockets.

Since, as shown by Fig. 4, the total range of the angle of lag of theeccentricity, is this device permits the designer to choose arbitrarily:

(1) A minimum rotative speed at which the device becomes operative.

(2) A low speed range, below the critical speed, over which the angle oferror is always less than 45.

(3) A high speed range, above the critical speed, over which the angleof error is always less than 45.

(4) The transition speed between these two ranges.

Obviously, if the added complication were Justified, three or moreconduits entering the balancing pockets could be used, thereby givingfurther freedom to the designer.

The modification shown in Figs. 9, l0, l1 and 12 is essentially the sameas that above described and differs from it only in that instead ofusing gravity to divert the balancing fluid into one of the two conduitsleading to each of the balancing pockets, spring biased deflecting vanesresponsive to a selected centrifugal force are resorted to and also afloating, self-centering supply ring.

Both of these changes are required for the reason that this modificationis designed to rotate on a horizontal axis rather than a vertical axis.

In this modification the rotor or basket I08 is fixed to the outer endof a free spindle shaft I09 in accordance with conventionalconstruction. Surrounding the basket is a shell III sealed at its outerend to the basket and forming at its inner end, an annular end wall I I2spaced from the head II3 of the basket. Disposed between the basket I03and the shell III are a number of longitudinally extending partitions II4 serving to define an equal number of balancing pockets II5a. to II5f.Mounted on the basket head H3 and forming an integral part thereof is adistributing disk IIII divided by spiral vanes II'I into spiral channelsII8a to II8I. These channels are provided with inlet ports 90. to I I9frespectively at their inner ends and at their outer ends withcorresponding discharge ports mm to I Disposed between the basket headH3 and the end wall H2 is an annular plate or ring I22. Extendingbetween the basket head H3 and the ring I22 are bafiles I23 defining aseries of angularly ofiset conduits I24a to I24] communicating at theirouter ends respectively with the balancing po'ckets IISq. to H5) and attheir inner ends respectively subtending the discharge ports I2Ila. toI20}. Extending between the ring I22 and the wall II2 are a series ofangularly offset baffies I25 defining a series of conduits I26a to I261,respectively communicating at their outer ends with the balancingpockets II5f to H511 and terminating at their inner ends in open sectorsrespectively subtending the distributing disk discharge ports I20a toI20]. It should here be noted that the ring I22 is in substantiallongitudinal alignment with the discharge ports I211. The structure sofar described is identical with the structure illustrated in Figs. 7 and8 with the single exception that it is designed to rotate on ahorizontal axis rather than on a vertical axis.

Journaled on the ring I22 for rotation in rectangular recesses I2!formed therein directly opposite each of the discharge ports I20 aredefiecting louvers I28a to I28 Each of these louvers is provided at eachend thereof with an outwardly extending weight I29 and with a biasingspring I3I normally holding their louvers in the position shown in Fig.9 at basket speeds below the transition speed. In this position of thelouvers water slung from the discharge ports of the distributing diskpasses into the balancing pockets through the outer conduits I24. Atspeeds above the transition speed the centrifugal force acting on theweights I29 is sufficient to force the louvers I28 against the biasingaction of their associated springs to the position shown in Fig. 12. Inthis position balancing fluid slung from the distributing disk isdeflected to the right as shown in Fig. 12 and therefore passes into thebalancing pockets through the inner series of conduits I26. Here then anadditional angle of lag 5 is given to the balancing fluid under theinfluence of centrifugal force rather than under the influence ofgravity as in the first modification described.

Mounted on brackets I33 extending inwardly from the basket frame arespring fingers I34 and supported by these fingers is a ring I35. Mountedon this ring by pins I35 extending therethrough is a clamping ring I31,this ring being biased toward the ring I35 by springs I38. Clampedbetween the two rings I35 and I31 is supply ring carrier I39 and fixedthereto is a balancing fluid supply ring I4I communicating through ahose I42 with a suitable source of balancing fluid. As in themodifications previously descnbed the inner wall I43 is arranged normanyto ,close the inlet ports I I9 of the distributing disk. As a result ofthis construction the supply ring MI is restrained against rotation, andis free to nod with the basket in sealing engagement therewith as inthe. case 01 the first modification and in addition to this isself-centering. When the extractor is first started romating theeccentricity of rotation increases, due to unbalance. If the supply ringI4I does not happen to-oe centered relative to the neutral position ofthe shaft, the eccentricity of rotation v will increase until it equalsthe radial clearance I44 between the shaft I09 and the supply ring I4IThe high side" of the shaft will then strike the supply ring, sliding itand the carrier ring I39 between the friction shoes I45 and I46respectively mounted on the rings I35 and I31, in such a direction as totend to center the supply ring. As the balancer becomes operative itdecreases the eccentricity of rotation until it is less than the radialclearance I44 and the shaft I09 no longer touches the supply ring I4I.This then leaves the supply ring in the desired centered positionrelative to the neutral position of the shaft. By resorting to thisexpedient, compensation is made for the particular neutral position ofthe shaft which of course depends upon the load to which the baskethappens to be subjected.

In so far as the balancing function of this modification is concerned.its operation is identical to the operation of'the modificationillustrated in Figs. 7 and 8.

In both modifications the balancing fluid in passing through thedistributing disk is deflected in a direction opposite to the directionof rotation of the basket through the angle of distribution a of thedistributing disk. In addition to this, the balancing fiuid slung fromthe distributing disk can be given a further angle of lag s either plusor minus depending upon whether the basket is rotating below or aboveits transition speed.

For convenience of definition the terms radius of eccentricity andradius of unbalance are used in several of the claims. By radius ofeccentricity is meant that radius drawn from the fixed reference axis(1. e., the axis 0" in the drawings) through the axis of the rotor (i.e., the axis C in the drawings.) By radius of unbalance is meant thatradius drawn from the fixed reference axis through the center of gravityof the unbalancing weight. Also, as used herein, the term light side, asapplied to an unbalanced rotor, is meant that portion of the rotor whichis located more than from'the center of gravity of the unbalancingweight. correspondingly, the heavy side is that portion which is lessthan 90 from the center of gravity of the unbalancing weight.

The functions of the extractors in which my automatic balancer has beenembodied, as above described, need no explanation. As extractors per sethey operate in accordance with principles well known in the industry.

I claim:

1. An automatically balancing rotor comprising: a frame; a shaft mountedon said frame for gyration about a reference axis; a rotor fixed to saidshaft coaxially and for rotation there- 11 with; fluid receivingbalancing pockets formed on the periphery of said rotor; a fluiddistributor mounted on said rotor for coaxial rotation therewith, saiddistributor being symmetrically divided by spiral vanes into spiralsections angularly offset from their inner to their outer ends, each ofsaid sections being provided on its inner end with an inlet port and onits outer end with a discharge port angularly offset with respect tosaid inlet port; conduits mounted onsaid rotor with their inner endslying adjacent to and in substantial angular alignment with saiddischarge ports and with their outer ends in communication with saidpockets; and automatic valve means associated with said rotor andresponsive to the eccentricity of said rotor for selectively deliveringbalancing fluid to one of said distributor sections.

2. An automatically balancing rotor comprising: a frame; a shaft mountedon said frame for gyration about a reference axis; a rotor fixed to saidshaft coaxially and for rotation therewith;

fluid receiving balancing pockets formed on the periphery of said rotor;a fluid distributor mounted on said rotor for coaxial rotationtherewith, said distributor being symmetrically divided by spiral vanesinto spiral sections angularly offset from their inner to their outerends, each of said sections being provided on its inner end with aninlet port and on its outer end with a discharge port angularly offsetwith respect to said inlet port; conduits mounted on said rotor withtheir inner ends lying adjacent to and in substantial. angular alignmentwith said discharge ports and with their outer ends in communicationwith said pockets; and automatic valve means associated with said rotorand responsive to the eccentricity of said rotor for selectivelydelivering balancing fluid to one of said distributor sections.

3. An automatically balancing rotor comprising: a frame; a shaft mountedon said frame for gyration about a fixed reference axis; a rotor flxedto said shaft coaxially and for rotation therewith; fluid receivingbalancing pockets Y formed on the periphery of said rotor; asectionalized fluid distributor formed on said rotor, each of thesections thereof being provided with an inlet port and a discharge portangularly offset with respect to said inlet port of said rotor; conduitsmounted on said rotor, said conduits communicating at their outer endswith said balancing pockets and terminating at their inner ends inintake openings spaced from but in angular alignment with said dischargeports so as to receive balancing fluid slung therefrom; and an automaticvalve associated with said rotor for selectively delivering balancingfluid to one of the sections of said distributor in response to theradial movement of said shaft.

4. An automatically balancing rotor comprising: a frame; a shaft mountedon said frame for gyration about a flxed reference axis; a rotor fixedto said shaft coaxially and for rotation therewith; fluid receivingbalancing pockets formed on the periphery of said rotor; a sectionalizedfluid distributor formed on said rotor, each of the sections thereofbeing provided with an inlet port and a discharge port angularly offsetwith respect to said inlet port; conduits mounted on said rotor, saidconduits communicating at their outer ends with said balancing pocketsand terminating at their inner ends in intake openings spaced from butin angular alignment with said discharge ports so as to receivebalancing fluid slung therefrom; and an automatic valve associated withsaid rotor for selectively delivering balancing fluid to one of thesections of said distributor in response to the radial movement of saidshaft.

5. A centrifugal extractor comprising: a frame; a shaft mounted on saidframe for gyration about a flxed reference axis; an extractor basketflxed to said shaft coaxially .and for rotation therewith; fluidreceiving balancing pockets formed on the periphery of said basket; asectionalized fluid distributor formed on said basket, each of thesections thereof being provided with an inlet port and a discharge portangularly offset with respect to said inlet port; conduits mounted onsaid basket, said conduits communieating at their outer ends with saidbalancing pockets and terminating at their inner ends at a point spacedfrom but in angular alignment with said discharge ports so as to receivebalancing fluid slung therefrom; and an automatic valve associated withsaid distributor for selectively delivering balancing fluid to one ofthe sections of said distributor in response to the radial movement ofsaid shaft.

6. An automatically balancing rotor comprising: a frame; a shaft mountedon said frame for gyration about a fixed reference axis; a rotor flxedto said shaft coaxially and for rotation therewith; a series of fluidreceiving balancing pockets formed on the periphery of said rotor; afluid distributor mounted on said rotor for coaxial rotation therewith,said distributor being divided by vanes into symmetrical sections, eachof said sections being provided on its inner end with an inlet port andon its outer end with a discharge port angularly offset with respect tosaid inlet port; a series of pairs of longitudinally adjacent conduitsmounted on said rotor, the inner ends of each pair of conduitssubtending one of the discharge ports of said distributorand the outerends thereof communicating respectively with different members ofsaidseries of balancing pockets; an automatic valve associated with saidrotor for selectively delivering balancing fluid to one of saiddistributor sections in response to gyration of said rotor; and meansfor diverting balancing fluid slung from said discharge ports to eitherone or the other of a pair of said conduits selectively in response tothe speed of rotation of said rotor.

7. An automatically baancing rotor comprising: a frame; a shaft mountedon said framehfor gyration about a flxed reference axis; a rotor fixedto said shaft coaxially and for rotation therewith; a series of fluidreceiving balancing pockets formed on the periphery of said rotor; afluid distributor mounted on said rotor for coaxial rotation therewith,said distributor being divided by vanes into symmetrical sections, eachof said sections being provided on its inner end with an inlet port andon its outer end with a discharge port angularly offset with respect tosaid inlet port; a series of pairs of longitudinally adjacent conduitsmounted on said rotor, the inner ends of each pair of conduitssubtending one of the discharge ports of said distributor and the outerends thereof communicating respectively with different members of saidseries of balancing pockets; an automatic valve associated with saidrotor for selectively delivering balancing fluid to one of saiddistributor sections in response to gyration of said rotor; and meansfor diverting balancing fluid slung from said discharge ports to eitherone or the other of a pair 13 of said conduits selectively in responseto the speed of rotation of said rotor.

8. An automatically self-balancing rotor comprising: a frame; a shaftmounted on said frame for gyration about a vertical reference axis; arotor fixed to one end of said shaft coaxially and for rotationtherewith; fluid receiving balancing pockets formed on the periphery ofsaid rotor; a fluid distributor mounted on said rotor for coaxialrotation therewith, said distributor being divided into symmetricalsections spiraling outwardly; a series of pairs of upper and lowerconduits mounted on said rotor for rotation therewith, the inner ends ofeach pair of conduits being adjacent to and in substantial angularalignment with one of said discharge ports, the outer ends of theconduits forming each pair of conduits being in communication withdifferent and peripherally spaced balancing pockets, and the lower wallsof said lower conduits extending inwardly beyond the lower wall of saidupper conduits; and automatic valve means mounted on said rotor andresponsive to the eccentricity of said rotor for selectively deliveringbalancing fluid to one of said distributor sections.

9. An automatically self-balancing rotor comprising: a frame; a shaftmounted on said frame for gyration about a vertical reference axis; arotor fixed to one end of said shaft coaxially and for rotationtherewith; fluid receiving balancing pockets formed on the periphery ofsaid rotor; a fluid distributor mounted on said rotor for coaxialrotation therewith, said distributor being divided into symmetricalsections spiraling outwardly in a direction opposite to the direction ofrotation of said rotor; a series of pairs of upper and lower conduitsmounted on said rotor for rotation therewith, the inner ends of eachpair of conduits being adjacent to and in substantial angular alignmentwith one of said discharge ports, the outer ends of the conduits formingeach pair of conduits being in communication with different andperipherally spaced balancing pockets, and the lower walls of said lowerconduits extending inwardly beyond the lower wall of said upperconduits; and automatic valve means mounted on said rotor and responsiveto the eccentricity of said rotor for selectively delivering balancingfluid to one of said distributor sections.

10. An automatically self-balancing rotor comprising: a frame; a shaftmounted on said frame for gyration about a reference axis; a rotor fixedto said shaft coaxially and for rotation therewith; fluid receivingbalancing pockets formed on the periphery of said rotor; a fluiddistributor mounted on said rotor for coaxial rotation therewith, saiddistributor being divided into channels spiraling outwardly, and each ofsaid channels being provided at its inner end with a fluid inlet portand at its outer end with a discharge port: a louver pivoted on saidrotor adjacent to and in radial alignment with each of said dischargeports, said louvers being weighted and springbiased so as to assume apredetermined deflected position at rotor speeds below a selected speedand to assume a different deflecting position under the influence ofcentrifugal force operating on the louver weights at speeds above saidselected speed; a series of pairs of longitudinally adjacent conduitsmounted on said rotor having inner ends in radial alignment with saidlouvers and outer ends communicating respectively with differentperipherally spaced balancing pockets; and an automatic valve mounted onsaid rotor and responsive to the eccentricity of said rotor forselectively delivering balancing fluid to one of said distributorchannels.

11. An automatically self-balancing rotor comprising: a frame; a shaftmounted on said frame for gyration about a. reference axis; a rotorfixed to said shaft coaxially and for rotation therewith; a balancingfluid distributing disk ed to said rotor coaxially therewith, said diskbeing 'formed with a series of radially extending fluid channels eachhaving an intake port at its inner end and a discharge port at its outerend; a balancing fluid supply ring disposed in sealing engagement withsaid distributing disk; means for holding said supply ring coaxial withsaid reference axis and against rotation, but permitting it to nod inresponse to the gyration of said rotor, said supply ring serving toclose all of the inlet ports of said distributing disk when said rotoris coaxial with said reference axis and to open one or more of saidinlet ports in response to the gyration of said rotor; a series oflongitudinally extending, peripherally spaced fluid receiving, balancingpockets formed on the periphery of said rotor; and a series of pairs ofconduits formed on said rotor substantially in the plane of saiddistributing disk, each pair of conduits having inner ends disposedadjacent one of the discharge ports of said distributing disk for thereception of balancing fluid therefrom, and outer ends communicatingrespectively with different and peripherally spaced members of saidseries of balancing pockets.

12. An automatic, self-balancing rotor comprising: a frame; a shaftmounted on said frame for gyration about a reference axis; a rotor fixedto said shaft coaxially and for a rotation therewith; a balancing fluiddistributing disk fixed to said rotor coaxially therewith, said diskbeing formed with a series of radially extending fluid channels eachhaving an intake port at its inner end and a discharge port at its outerend angularly offset from its associated inlet port; a balancing fluidsupply ring mounted on said frame in sealing engagement with saiddistributing disk and for radial movement in response to the gyration ofsaid shaft, said supply ring serving to close all of the inlet ports ofsaid distributing disk when said rotor is coaxial with said referenceaxis and to open at least one of said inlet ports in response to thegyration of said rotor; means for dampening the radial movement of saidsupply ring; a, series of longitudinally extending, peripherally spacedfluid receiving balancing pockets formed on the periphery of said rotor;and a series of pairs of conduits formed on said rotor substantially inthe plane of said distributing disk, each pair of conduits having innerends disposed adjacent one of the discharge ports of said distributingdisk for the selective reception of balancing fluid therefrom, and outerends communieating respectively with different and selected members ofsaid series of balancing pockets.

13. A centrifugal machine comprising: a frame; a shaft mounted on saidframe for gyration about a fixed reference axis; a rotor fixed to saidshaft coaxially and for rotation therewith; fluid receiving balancingpockets formed on the periphery of said rotor; a sectionalized fluiddistributor formed on said rotor, each of the sections thereof beingprovided with an inlet port and a discharge port angularly oifset withrespect to said inlet port; a balancing fluid supply ring disposed insealing engagement with said fluid distributor; means for holding saidsupply ring 15 coaxial with .said neference axis and against rotation;conduits mounted on said rotor, said conduits communicatingat theirouter ends with said balancing pockets and terminating at their innerends in openings subtcnding each of said discharge ports but radiallyspaced therefrom.

14. In 'a dynamically balancedmachine of the character describedcomprising a rotor mounted for rotation about its axis and for gyrationabout a flxed reference axis in response to an unbalancing weight, andbalancing means therefor including fluid supply means and fluidreceiving means .for eceiving from said supply means a balancing fluidto counterbalance the unbalancing weight, the improvement whichcomprises means responsive to and operated by the speed of the rotor forchannelling the supply of balancing fluid passing from said supply meansto said receiving means in accordance with the angle of lag between theradius of eccentricity and the radius of unbalance, to add balancingfluid at speeds above the critical speed to a sector or said receivingmeans located not less than 90 from the radius of unbalance.

15. In a dynamically balanced machine of the character describedcomprising a rotor mounted for rotation about its axis and for gyrationabout a fixed reference .axis in response to an unbalancing weight, andbalancing means including automatic valving means operated byeccentricity of the rotor to provide a supply of balancing fluid to adistributing member, and balancing compartments arranged about the rotoraxis to receive balancing fluid from said distributing member tocounterbalance the unbalancing weight, the improvement which comprises aselective distributing member capable of channelling balancing fluid tosaid compartments and operated by and in response to the speed of therotor to select a compartment to receive the balancing fluid so as toadd the fluid at a point not less than 90 from the radius of unbalance.

16. In a rotating system of the character described. including a rotormounted for rotation about its own axis and for gyration about a fixedreference axis coinciding with the rotor axis when the rotor isdynamically balanced, said system having the characteristic ofgyrating'with the heavy side out at speeds below the critical speed andwith the light side out at speeds above the critical speed of thesystem, the improvement which comprises automatic balancing meanscontrolled and operated by eccentricity and speed of the rotor formaintaining a supply of balancing fluid on the light side of the rotorover a wide range of speeds including speeds above the critical speed.

17. In a rotating system of the character described, including a rotormounted for rotation about its own axis and for gyration about a fixedreference axis coinciding with the rotor axis when the rotor isdynamically balanced, said system having the characteristic of gyratingwith the heavy side out at speeds below the critical speed and with thelight side out at speeds above the critical speed of the system, theimprovement which comprises automatic balancing means including valvemeans automatically operated in response to eccentricity of the rotor toprovide a supply of balancing fluid, and fluid distributing meanscontrolled and operated by the speed of the rotor for maintaining asupply of balancing fluid on the light including speeds above thecritical speed of the system.

18. In a rotating system of the character described, includlng a rotormounted for rotation about its own axis and for gyration about a flxedreference axis coinciding with the rotor axis when the rotor isdynamically balanced, said system having the characteristic of gyratingwith the heavy side out at speeds below the critical speed and with thelight side out at speeds above the critical speed of the system, theimprovement which comprises automatic balancing means includingbalancing compartments arranged about the rotor axis to receivebalancing fluid, valve means automatically operated in response toeccentricity of the rotor to provide a supply of balancing fluid forsaid compartments and fluid distributing means controlled by the speedof the rotor for distributing balancing fluid to one or more'of saidcompartments on the light side of the rotor over a wide range of speeds,including speeds above the critical speed of the system, saiddistributing means comprising upper and lower channels communicatingwith different balancing compartments, said upper channels receivingbalancing fluid at relatively high rotor speeds and said lower channelreceiving balancing fluid at relatively low rotor speeds.

19. In a rotating system of the character described, including a rotormounted for rotation about its own axis and for gyration about a fixedreference axis coinciding with the rotor axis when the rotor isdynamically balanced, said system having the characteristic of gyratingwith the heavy side out at speeds below the critical speed and with thelight side out at speeds above the critical speed of the system, theimprovement which comprises automatic balancing means includingbalancing compartments arranged about the rotor axis to receivebalancing fluid, valve means automatically operated in response toeccentricity of the rotor to provide a supply of balancing fluid forsaid compartments and fluid distributing means controlled by the speedof the rotor for maintaining a supply of balancing fluid on the lightside of the rotor over a wide range of speeds including speeds above thecritical speed of the system. said distributing means comprisingcentrifugally operated valves arranged to channel balancing fluid to oneor another of said compartments according to the speed of the rotor andthe centrifugal force exerted thereby upon the valves.

20. In an automatically balancing rotating system of the type comprisinga rotor mounted to rotate about its own axis and to gyrate about a fixedreference axis in response to an unbalancing weight, balancing meansarranged about the rotor axis to receive balancing fluid, anddistributing means for selectively distributing balancing fluid to saidbalancing means to correct a condition of unbalance, the improvementwhich comprises automatic valving means for admitting balancing fluidfrom a source thereof to said distributing means, said automatic valvingmeans comprising a valve member non-rotatably flxed to the frame of themachine and a co-operable valve member flxed to the rotor for rotationtherewith, said valve members being automatically operated in responseto deflection of the rotor to open when the rotor is deflected and toclose when the rotor is dyside of the rotor over a wide range of speeds,I" namically balanced.

21. An automatically balancing rotating system comprising a rotormounted to rotate about its own axis and to gyrate about a fixedreference axis, balancing compartments arranged about the rotor axis toreceive balancing fluid,

and valve and distributor means for supplying balancing fluid to saidcompartments, said valve and distributor means comprising a nonrotatablevalve member fixed to the frame of the machine and having an annularpassage defined by side walls and a rotable valve and distributor memberfixed to the rotor for rotation therewith, said rotatable membercomprising a ,plurality ofchannels each communicating with a selectedcompartment, said rotatable member also comprising a bottom closure insealing engagement with the walls of said annular passage, said bottomclosure being formed with a hole for each channel which is closed by awall of said annular passage when the rotor is balanced, one or more ofsaid holes being uncovered and communicated with said annular passagewhen the rotor is deflected.

22. An automatically balancing machine of the character described,comprising a rotor mounted for rotation about its axis and for gyrationabout a fixed reference axis in response to an unbalancing weight, fluidreceiving means arranged to receive balancing fluid to counterbalancesaid unbalancing weight, fluid supply means operated by eccentricity ofthe rotor for supplying balancing fluid to said fluid receiving meansand alternate channelling means including a first set of channelsarranged to channel fluid from said supply to said receiving means and asecond set of channels arranged to channel fluid from said supply meansto said receiving means, said first set being so arranged as to channelfluid at speeds below critical speed to a sector of said receiving meansopposite the deflected side of the rotor and opposite the heavy side ofthe rotor and said second set being so arranged as to channel fluid atspeeds above critical speed to a sector of said fluid receiving means onthe deflected side of the rotor and opposite the heavy side of therotor.

23. An automatically balancing machine of the character described,comprising a rotor mounted for rotation about its axis and for mationabout a fixed reference axis in response to an unbalancing .weight,fluid receiving means arranged to receive balancing fluid tocounterbalance said unbalancin weight, fluid supply means operated byeccentricity of the rotor for supplying balancins nei fluid to a sectorof said receiving means more I fluid to said fluid receiving andcentriiugally operated channelling means for selectively channellingbalancing fluid, said; channelling means comprising: a first set ofchannels each having an inlet communicating with said fluid su ply meansand an outlet communicating with a sector of said fluid receiving means;said channelling means also comprising a second set of channels eachhaving an inlet in'registry with the inlet of one of said first set ofchannels and a iifoutlet communicating with a digerent sector of saidfluid receiving means; andnieans operated automatically by centrifugalforce for directing fluid from said supply means to said flrst set ofchannels at speeds below critical speed and to said second set ofchannels at speeds above the: critical speed; the outlet ends of 'saidfirst and second sets of channels being angularly displaced such thatfluid will be delivered by the first set opposite the deflected side andthe heavy sid of the rotor, and such that fluid will be delivered bye-te second set to the deflected .side and opposite the heavy side of therotor.

24. An automatically balancing machine comprising a rotor mounted forrotation about its axis and for gyration about a fixed reference axis inresponse to a condition of unbalance, fluid supply means responsive toand operated by eccentricity of the rotor for supplyinga balancing tocorrect said condition of unbalance, fluid receiving means arrangedabout said'axis of rotation to receive said-fluid. and channelling meansfor receiving said fluid from said supply means 1 channelling it to saidreceiving in'eans, said channelling means being responsive; to andoperated by centrifugal force created by rotation at-;speeds above thecritical speedso as to chantl'ian from theradius of unbalance.

ERNEST L. THEARLE.

REFERENCES CITED I The following references are or record in the die ofthis patent:

UNITED STATES PATENTS

